Our recently synthesized ligands, such as diamides of cis-1, 2- cyclohexanedioxydiacetic acid, preferentially chelate cations in the order: Ca ions much greater than Ba ions much greater than Sr ions much greater than Mg ions greater than Na ion, K ion. Our data indicates that the ligands are also good: (a) in two-phase extraction and three-phase transport (model membrane systems), (b) as substrates in ion-selective electrodes (data by Professor Wilhelm Simon, ETH, Zurich), and (c) in releasing calcium from heart muscle tissue and thus possibly of value in cardiovascular drug research. The chemical work in our laboratory establishes the relative strength of chelation of a ligand for various cations by using either instruments (ultra-violet and spectroscopy) or picrate extraction techniques. In the coming year we hope to define the structure of the complexes formed for our most effective ligands with calcium or barium salts and to design ligands which exceed the presently found selectivity for calcium vs. sodium or potassium of ca 50/1 while retaining good transport and lipophilic properties. Our ligands are biologically tested by a research cardiologist at Baylor University College of Medicine and a biochemist at Queens College, City University of New York.